1. Field of the Invention
This invention relates to an apparatus and method for manipulating a guidewire and connecting the guidewire to an extension guidewire.
2. Description of the Related Art
Medical guidewires generally are used for navigating through internal passageways of a body. The distal end of a guidewire is introduced into a body by a physician through an opening in the body. The physician manipulates the tip of the guidewire through the body to a site to be treated. A catheter or other medical device is usually advanced over the guidewire to the treatment site. In some medical applications, it is desirable to use multiple catheters sequentially in order to complete the medical procedure. When it is necessary to change catheters, it is usually preferred that the catheter be removed in a manner which enables a guidewire to remain in place in the body so that the end of the guidewire remains on the site to be treated. In order to maintain a guidewire in place while withdrawing the catheter, the guidewire must be gripped at its proximal end to prevent it from being pulled away from the site to be treated, for example, a blood vessel. However, the guidewire typically only extends for a short portion outside of the catheter which is inserted in the body. Therefore, before the catheter is fully withdrawn from the body, the catheter completely covers the proximally extending end of the guidewire. As a result, there is no way in which to grip the proximal end of the guidewire to hold it in place and prevent it from being withdrawn together with the catheter.
One method which has been proposed for solving the above catheter exchange problem is the use of an exchange wire. In such a method, the existing guidewire is removed and replaced by a longer exchange wire. The removal and replacement occurs with the existing catheter in place. Unfortunately, the insertion of each additional wire significantly increases the risk of trauma and puncture to the patient and extends the duration of the procedure.
Another common method is the use of an extension guidewire. This has improved the procedure for performing a catheter exchange. An extension guidewire allows a catheter exchange to be made without any guidewire exchanges. In this way, there is a significant reduction in risk of puncturing blood vessels in the body, and a reduction in the time to perform the procedure. However, current apparatus and methods for steering the main guidewire into the body and then connecting the main guidewire to an extension guidewire to perform a catheter exchange have certain drawbacks.
Current extension guidewire methods require the use of a separate apparatus for steering the main guidewire into the body and a separate apparatus for aligning and connecting the main guidewire with an extension guidewire. Typically, a torque vise or pin vise is provided for gripping the main guidewire and steering the main guidewire into the human body. The main guidewire is often provided with an angled tip so that the operator can rotate the main guidewire and steer the main guidewire through the body. The torque vise can be slid back along the main guidewire to permit advancement of the main guidewire relative to the torque vise in order to insert the main guidewire further into the human body. Once the main guidewire and catheter are in place, it is often necessary to perform a catheter exchange.
Typically, an alignment tool functions to connect the proximal end of the in-situ guidewire to an extension guidewire. The torque vise is first removed from the in-situ guidewire. The alignment tool is then placed on the in-situ guidewire and used to align and connect the in-situ guidewire with an extension guidewire. After the in-situ guidewire and extension guidewire are connected, the alignment tool is removed. The alignment tool is removed by sliding the alignment tool proximally over the portion of the in-situ guidewire located in the alignment tool and then over the extension guidewire. The existing catheter in the body is then drawn proximally over the entire length of the in-situ and extension guidewire, and then replaced by a new catheter by sliding the new catheter distally over the entire length of the extension guidewire and in-situ guidewire. The extension guidewire then can be disconnected once the new catheter is in place.
This process of using a separate torque vise and alignment tool is cumbersome and significantly increases the amount of time for performing such operations. The amount of time spent on such operations can significantly increase the risk to a patient. Moreover, the use of separate apparatus for steering the main guidewire and for connecting the main guidewire to an extension guidewire makes the operation more complex, thus leading to more opportunities for mistakes or movement of the in-situ main guidewire during a catheter exchange. In addition, each tool must be separately manufactured, packaged and handled, increasing cost, for example. Therefore, for the above reasons, the current apparatus and methods for steering a main guidewire and connecting the main guidewire to an extension guidewire are less than desirable. There is a need for an apparatus and method for steering a main guidewire and connecting the main guidewire to an extension guidewire which substantially obviates these problems.